Vertical automatic drying and roasting furnace



Patented Ian. 2, I900.

Nu. 640,7I5. I

J. STOVEKEN. VERTICAL AUTOMATIC DRYING AND BOASTING FURNACE.

(Application filed June a, 1898.

2 Shoots-Sheet (No Model.

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No. 640,7!5. Patented Ian. 2, 1960. J. STOVEKEN.

VERTICAL AUTOMATIC DRYIN G AND ROASTING FURNACE.

(Application filed June 3, 1899.) (No Model.) 2 Shouts-Sheet 2.

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PATENT JOHN STOVEKEN, OF MILWAUKEE, WVISCONSIN.

SPECIFICATION forming part of Letters Patent No. 640,715, dated January 2, 1900.

' Application filed June 3, l899 Serial No. 719,200. (No model.)

To all whom it may concern:

Be it known that I, JOHN STOVEKEN, a citizen of the United States of America, resid- "ing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and nsefullmprovements inVertical Automatic Drying and Roasting Furnaces and I do declare the following to bea full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had tothe accompanying drawings, and to the figures of reference marked thereon, which form a part of this specification.

My invention relates to improvements in automatic roasting or oxidizing furnaces of the upright stack or vertical type adapted for roasting or dryingores.

My object is to provide a device of this class which shall be simple in construction, economical in cost, and continuous in operation and which shall possess the highest degree of efficiency in the performance of its functions.

To these ends the invention consists of the features, arrangements, and combinations hereinafter described and claimed, all of which will be fully understood by reference to the accompanying drawings, in which is illustrated an embodiment thereof.

In the drawings, Figure 1 is a vertical longitudinal section of my improved furnace, taken on the line X X, Fig. 2. Fig. 2 is a similar section taken on the line Y Y, Fig. 1. Fig. 3 is a cross-section taken on the line A B, Figs. 1 and 2. Figs. 4: and 5 are horizontal sections taken on the lines 0 D and E F, respectively, Figs. 1 and 2. Fig. 6 is a top or plan view of the furnace.

right columns of ore, having two feed-openings at the top and two discharge-openings at the bottom. It must be understood, however, that I do not limit the invention to the double structure, as the single'form is equally within the scope of the invention.

The bottom of the vertical oxidizing-cham ber where the ore is discharged is troughshaped, as shown at 27, the bottom of each trough being provided with an outlet-open ing, into which the ore is discharged by an upright cast-iron pipe 8, suitably supported above the opening by a channel-beam 4. (See Fig. 2.) Each discharge-opening in the bottom of the furnace communicates with a chamber 9, in which is located a table or platform 10, over which passes an endless dragchain 12, supported by wheels 13, which are propelled by any suitable power. The chain 12 travels in the direction indicated by the arrows in Fig. 2 and carries the roasted ore into a trough 14, from which it may be removed in any suitable manner.

The upper extremity of each discharge-pipe 8 is funnel-shaped and located directly below a series of inclined shelves 15, extending crosswise of the furnace and supported by the vertical walls thereof, a sufficient space being left on both sides of the shelves to allow the heat to pass upward in the vertical chamber from the bottom to the top. These shelves 15 are arranged in two rows and located on opposite sides of a central vertical line passing through a discharge-pipe 8, the individual shelves on opposite sides of this line being staggered or alternately arranged with reference to each other, whereby the ore in passing downward will slide from a shelf on one side to the next lower shelf on the opposite side, these two shelves occupying a position preferably at right angles or approximately at right angles to each other. By this arrangement the ore which was underneath or in contact with the shelf on one side is uppermost or exposed to the heat when it reaches the opposite shelf, whereby the ore is evenly roasted or oxidized. These shelves 15 extend from the top of the discharge-pipes 8 to pipes 16, forming muffles in the upper portion of.

the roasting-chamber. The lower shelves are desirable material may be employed for this purpose. The muffle roast-pipes 16 are preferably provided with interior inclined ledges 16, and they may be provided with openings located at suitable intervals from which lead upwardly-projecting tubes 16, which permit the escape of the vapor from the ore in the mufiies. These outlet orifices and tubes may be used or not, as desired. As shown in the drawings, the muiiie-pipes are constructed of sections or lengths of diiferent diameters, these sections increasing in size from the top downward, whereby the passage of ore therethrough is facilitated. They are supported by suitable horizontal beams or bars 17, whose extremities are supported by the vertical walls of the roasting-chamber.

Into the top of each motile-pipe 16 projects an inlet-pipe 18, whose upper extremity communioates with a hopper 19, projecting above the top of the vfurnace. One of these hoppers is located on each side of the central stack 20, through which the products of combustion escape from the roasting-chamber. The portion 21 of the vertical wall (indicated by dotted lines in Fig. 1) is constructed separately from the body of the wall, whereby the bricks may be readily removed to form an opening giving access to the furnace-chamber when for any reason such access maybe necessary or desirable. On opposite sides of the central ore-supporting shelves 15 the walls of the furnace are provided at suitable intervals with short upwardly-projecting ledges 22, whose function is the deflection of the heat inwardly toward the central ore-supportin g shelves 15, whereby the roasting or oxidizing efficiency of the structure is enhanced.

As shown in the drawings, the top of the furnace is closed except where the smokestack and the oreinlet pipes are located.

In using the furnace a fire sufficient to produce a heat of the desired intensity is made in the fire-box 7, whereby the heat passes therefrom upward through the vertical oxidizing-chamber 6, around the ore-supporting shelves 15 to the muffles 16. The ore fed into the top of the furnace through the hoppers 19 passes thence through the inlet-pipes 18 into the muffie roasting-pipes 16, and thence downward through the ore-shelves 15 and the discharge-pipes 18 to the bottom of the furnace, and thence through the openings therein to the platform 10, which forms a stop for the ore, which then begins to accumulate and pile upward in the furnace until there is a central vertical column of ore extending upward from the bottom to the top of the roasting-chamber, filling a pipe 8, covering the shelves 15, and filling a mufiie-pipe 16. If the furnace is of double construction, as shown in the drawings, there are two of these columns of ore formed in the furnace, one being substantially a duplicate of the other. Hence in describing the use and operation of the furnace only a single column will be referred to.

It is evident that the pipes 8 and 16 may be made of fire-clay instead of iron. In fact, with some classes of ore iron could not be used. Hence it will be understood that I do not limit myself to any special material in the construction of any part of the furnace.

Access may be gained to the ore-supporting shelves from the outside of the furnace through horizontal openings 25, formed in the vertical walls and normally closed by removable cast-iron plugs 26. These openings may be utilized to prevent the ore from clogging the furnace and also to remove samples of the ore for the purpose of learning its condition during the roasting operation.

The operation of the furnace is as follows: After the roastingchamber has been once charged with ore the dra -chain at the bottom is put in motion and the bottom of the ore column removed more or less slowly, according to the nature of the ore. The roasting of some ores requires much more time than oth ers. Hence the motion of the drag-chain will depend upon the character of the ore treated. The longer the time required for the roasting of the ore the slower will be the travel of the chain; but in any event the movement of the drag-chain is continuous, and the column of ore is continually moving downward to take the place of the ore carried away by the chain, the ore being fed in at the top to maintain the height of the column or keep the furnace continually and evenly charged to the limit of its capacity. The ore is continually moving downward at a speed to allow it to be properly roasted while passing from the top to the bottom of the furnace. The bottom of the ore column belonging to the first charge of ore will not be sufficiently roasted, since it has fallen directly from the top to the bottom of the furnace and has not been sufficientlyexposed to the oxidizing or roasting atmosphere. Hence the first ore removed by the drag-chain will need to be returned and passed again through the furnace; but after this the ore taken from the bottom of the column is properly roasted and the operation is continued without interruption.

Having thus described my invention, what I claim is- 1. The combination with a vertical oreroasting chamber having an ore-inlet at the top and a discharge-opening at the bottom, of means for maintaining a vertical column of ore between these two openings, and in a central position in the roasting chamber, whereby the heat is allowed to pass upward around the ore, said means comprising inclined shelves supported by the furnacewalls,and located in the lower part of the furnace,and muftles supported in the upper part of the furnace, the wall of the chamber being provided with openings opposite the ore supporting means to permit access to the column of ore, and detachable plugs normally closing said openings- 2. The combination with a vertical oreroasting chamber having an ore-inlet at the top and a discharge-opening at the bottom, of means for maintaining a vertical column of ore between these two openings and in a central position in the roastingchamber, said means comprising inclined shelves supported by the furnace-walls and located in the lower part of the furnace, muffles supported in the upper part of the furnace, and inclined, deflecting ledges attached to the inner walls of the furnace and adapted to direct the heat toward the central column of ore.

3. The combination with a vertical oreroasting chamber having an ore-inlet at the top and a discharge-opening at the bottom, of means for maintaining a vertical column of ore between these two openings and in a central position in the roasting-chamber, whereby the heat is allowed to pass upward around the ore, said means comprising inclined shelves supported. by the furnacewalls and located in the lower part of the furnace, and a muffle-pipe located in the upper part of the furnace-chamber and provided with orifices and upwardly-projecting tubes leading therefrom.

at. The combination with a vertical oreroasting chamber having an ore-inlet at the top and a discharge-opening at the bottom, of means for maintaining a vertical column of ore between these two openings and in a central position in the roasting-chamber, said means comprising inclined shelves supported'by the furnace-walls and located in the lower part of the furnace, and a mufflepipe located in the upper part of the furnacechamber and having inclined, staggered, inwardly-projecting ledges said muffle being also provided with orifices and upwardlyprojecting tubes leading therefrom.

5. The combination, with a vertical oreroasting chamber, having an ore-inlet at the top and a discharge-opening at the bottom, of means for maintaining a vertical column of ore between these two openings and in a central position in the roasting-chamber, whereby the heat is allowed to pass upward around the ore, said means comprising inclined shelves supported by the furnace-walls and located in the lower part of the furnace, and muftles supported in the upper part of the furnace.

6. In a vertical roasting-furnace, the combination with a vertical oxidizingchamber having an inlet-opening at its top and a discharge-opening at its bottom, of means for supporting a central, vertical column of ore in said chamber between said openings, said means comprising a vertical discharge-pipe located in the bottom of the chamber, inclined shelves located above said pipe and a vertical muftie-tube located above the shelves, the ore-column-supporting means being so located as to leave room for the hot air to pass upward from the bottom to the top of the furnace.

7. The combination with a vertical oreroasting chamber having an inlet-opening at the top and a discharge-opening at the bottom, of means for maintaining a vertical column of ore between these two openings and in a central position in the roasting-chamber, whereby the heat is allowed to pass upward around the ore, said means comprising inclined shelves supported by the furnacewalls and located in the lower part of the furnace, and muffies supported in the upper part of the furnace, a chamber located below the discharge-opening of the furnace, a platform or table locatedv in said chamber and forming a support for the ore column, and an endless drag-chain passing over said table or platform for removing the ore at the base, and causing a continuous downward movement of the ore column.

In testimony whereof I aflix my signature in presence of two witnesses.

JOHN STOVEKEN. WVitnesses:

A. J. OBRIEN, NELLIE G. DANIELS. 

